Clopidogrel nonresponsiveness varies according to duration of therapy

Relationship between frequency of patients and absolute change in aggregation (Δ Aggregation [percent]) in response to 5 μmol/L ADP at 2 hours, 24 hours, 5 days, and 30 days after stenting. Δ Aggregation (percent) is defined as baseline aggregation (percent) minus post-treatment aggregation (percent). Resistance, as defined herein, is Δ Aggregation (percent) ≤10 percent. Resistance is present in those patients subtended by double-headed arrow. Curves represent normal distribution of data and were created by Statistica software.